Year | Value | 2021 | 12.901 | 2020 | 13.071 | 2019 | 13.346 | 2018 | 13.708 | 2017 | 14.269 | 2016 | 15.161 | 2015 | 15.891 | 2014 | 16.19 | 2013 | 16.312 | 2012 | 16.509 | 2011 | 16.484 | 2010 | 16.854 | 2009 | 17.118 | 2008 | 17.048 | 2007 | 16.72 | 2006 | 16.637 | 2005 | 16.83 | 2004 | 17.127 | 2003 | 17.674 | 2002 | 18.35 | 2001 | 19.097 | 2000 | 19.585 | 1999 | 19.909 | 1998 | 20.236 | 1997 | 20.849 | 1996 | 21.502 | 1995 | 22.339 | 1994 | 22.972 | 1993 | 23.477 | 1992 | 23.71 | 1991 | 23.735 | 1990 | 23.883 | 1989 | 24.102 | 1988 | 24.429 | 1987 | 25.075 | 1986 | 25.825 | 1985 | 26.885 | 1984 | 28.053 | 1983 | 29.516 | 1982 | 30.222 | 1981 | 29.97 | 1980 | 29.866 | 1979 | 30.776 | 1978 | 30.803 | 1977 | 30.796 | 1976 | 31.368 | 1975 | 32.086 | 1974 | 32.859 | 1973 | 33.756 | 1972 | 34.589 | 1971 | 35.542 | 1970 | 36.45 | 1969 | 37.366 | 1968 | 38.339 | 1967 | 39.268 | 1966 | 40.17 | 1965 | 41.232 | 1964 | 42.449 | 1963 | 43.82 | 1962 | 45.703 | 1961 | 47.566 | 1960 | 49.257 |
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